diversity in this species. Moreover, allocthonous
seedling recruitment in two of the three localities suggests that habitat fragmentation is not
resulting in complete genetic isolation of populations. However, the genetic erosion observed in
this important species, also related to high levels
of inbreeding and possibly self-fertilization, can
result in a low capacity to deal with the more
rapid anthropogenic and climatic changes that
are under way in the Mediterranean basin.
Acknowledgements. The research was partially supported by
"C.N.R. Target Project on Biotechnology".
References
Caye G. Meinesz A (1992) Analyse des modalW!s de la multiplication vegetative et de la reproduction sexuee de Posidonia
oceanica et de ses consequences sur la constitution genetique des herbiers. Rapp Camm Int Mer Mediterr 33:32
Gambi MC, Buia MC, Mazzella L (1996) Record of a diffuse germination of Posidonia oceanica (L.) De1ile in the central
Adriatic Sea (Croatia). BioI Mar Mediterr 3(1): 467-470
Goldstein DB, Ruiz Linares A, Cavalli-Sforza L1, Feldman MW
(1995) Genetic absolute dating based on microsatellites and
the origin of the modern humans. Proc Natl Acad Sci USA
92: 6723-6727
Goodman SJ (1997) RST CALC: a collection of computer programmes for calculating unbiased estimates of genetic differentiation and determining their significance for
microsatelHte data. Mol Eco16: 881-885
Goudet J (1995) Fstat version 1.2: a computer programme to calculate F-statistics. J Hered 86: 485-486
Sexual Reproduction and Genetic Diversity in P. oceanica
389
Les DR (1988) Breeding systems,population structure and evolution in hydrophilous angiosperms. Ann Missouri Bot Gard
75: 819-835
Meinesz A, Caye G, Locques F, Molenaar H (1993) Polymorphism
and development of Posidonia oceanica transplanted from
different parts of the Mediterranean into the National Park
ofPort-Cros. Bot Mar 36:209-216
Piazzi L, Acunto S. Halestri E, Cinelli F (1996) Osservazioni preliminari sulla germinazione di semi e sviluppo in situ di
piantine di Posidonia oceanica (L.) Dellie. InfHot Ital28: 6166
Procaccini G, Alberte RS, Mazzella L (1996) Genetic structure of
the sea grass Posidonia oceanica in the Western
Mediterranean: ecological implications. Mar Ecol Prog Set
140: 153-160
Procaccini G, Mazzella L (1996) Genetic variability and reproduction in two Mediterranean seagrasses. In: Kuo J, Phillips RC,
Walker Dr, Kirkman H (eds) Seagrass biology. Proc Int
Workshop, Sciences UWA. Nedlands. Western Australia, pp
85-92
Procaccini G. Mazzella L (1998) Population genetic structure and
gene flow in the seagrass Posidonia oceanica (1.) assessed
using a microsatellite analysis. Mar Ecol Prog Ser 169: 133141
Procaccini G, Waycott M (1998) Microsatellite loci identified in
the seagrass Posidonia oceanica (L) Dellie. r Hered 89(6):
562-568
Raymond M, Rousset F (1995) GENEPOP (version 1.2): a population genetics software for exact tests and ecumenism. J
Hered 86: 248-249
Waycott M, Sampson J (1997) The mating system of an hydrophilous angiosperm Posidonia australis (Posidoniaceae).
Am J Bot 84(5): 621-625
Weir ES, Cockerham CC (1984) Estimating F-statistics for the
analysis of population structure. Evolution 38(6): 1358-1360
seedling recruitment in two of the three localities suggests that habitat fragmentation is not
resulting in complete genetic isolation of populations. However, the genetic erosion observed in
this important species, also related to high levels
of inbreeding and possibly self-fertilization, can
result in a low capacity to deal with the more
rapid anthropogenic and climatic changes that
are under way in the Mediterranean basin.
Acknowledgements. The research was partially supported by
"C.N.R. Target Project on Biotechnology".
References
Caye G. Meinesz A (1992) Analyse des modalW!s de la multiplication vegetative et de la reproduction sexuee de Posidonia
oceanica et de ses consequences sur la constitution genetique des herbiers. Rapp Camm Int Mer Mediterr 33:32
Gambi MC, Buia MC, Mazzella L (1996) Record of a diffuse germination of Posidonia oceanica (L.) De1ile in the central
Adriatic Sea (Croatia). BioI Mar Mediterr 3(1): 467-470
Goldstein DB, Ruiz Linares A, Cavalli-Sforza L1, Feldman MW
(1995) Genetic absolute dating based on microsatellites and
the origin of the modern humans. Proc Natl Acad Sci USA
92: 6723-6727
Goodman SJ (1997) RST CALC: a collection of computer programmes for calculating unbiased estimates of genetic differentiation and determining their significance for
microsatelHte data. Mol Eco16: 881-885
Goudet J (1995) Fstat version 1.2: a computer programme to calculate F-statistics. J Hered 86: 485-486
Sexual Reproduction and Genetic Diversity in P. oceanica
389
Les DR (1988) Breeding systems,population structure and evolution in hydrophilous angiosperms. Ann Missouri Bot Gard
75: 819-835
Meinesz A, Caye G, Locques F, Molenaar H (1993) Polymorphism
and development of Posidonia oceanica transplanted from
different parts of the Mediterranean into the National Park
ofPort-Cros. Bot Mar 36:209-216
Piazzi L, Acunto S. Halestri E, Cinelli F (1996) Osservazioni preliminari sulla germinazione di semi e sviluppo in situ di
piantine di Posidonia oceanica (L.) Dellie. InfHot Ital28: 6166
Procaccini G, Alberte RS, Mazzella L (1996) Genetic structure of
the sea grass Posidonia oceanica in the Western
Mediterranean: ecological implications. Mar Ecol Prog Set
140: 153-160
Procaccini G, Mazzella L (1996) Genetic variability and reproduction in two Mediterranean seagrasses. In: Kuo J, Phillips RC,
Walker Dr, Kirkman H (eds) Seagrass biology. Proc Int
Workshop, Sciences UWA. Nedlands. Western Australia, pp
85-92
Procaccini G. Mazzella L (1998) Population genetic structure and
gene flow in the seagrass Posidonia oceanica (1.) assessed
using a microsatellite analysis. Mar Ecol Prog Ser 169: 133141
Procaccini G, Waycott M (1998) Microsatellite loci identified in
the seagrass Posidonia oceanica (L) Dellie. r Hered 89(6):
562-568
Raymond M, Rousset F (1995) GENEPOP (version 1.2): a population genetics software for exact tests and ecumenism. J
Hered 86: 248-249
Waycott M, Sampson J (1997) The mating system of an hydrophilous angiosperm Posidonia australis (Posidoniaceae).
Am J Bot 84(5): 621-625
Weir ES, Cockerham CC (1984) Estimating F-statistics for the
analysis of population structure. Evolution 38(6): 1358-1360